# EXPERTSTATEMENT StudyTitle: HVDROL YSIS DETERMINATION OF DEA/Acid anhydride reaction productAT DIFFERENT pH VALUES Data RequirementITestGuidelines: OECD No. 111 EEC Directive 92/69, C.7 StudyDirector: Mrs. AlessandraTognucci StudyCompletion Date: February05, 2004 Test Facility: RCC Ltd Environmental Chemistry& Pharmanalytics CH-4452 ltingen/Switzerland Sponsor: RockwoollnternationalA/S Hovedgaden 584 DK-2640 Hedehusene Denmark RCC StudyNumber: 848638 Page 1 of9RCC Study Number 848638 DEN Acid anhydride reaction product Title: Sponsor:
Monitoring Scientist:

Expert Statement by: 

# STATEMENT EXPERT STATEMENT Hydrolysis Determination of DEAl Acid anhydride reaction product at Different pH Values Rockwool International A/S Hovedgaden 584 DK-2640 Hedehusene Denmark Mr. Flemming A. Simonsen Danish ToxicologyCentre Kogle Aile 2 DK-2970 H0RSHOLM Denmark Mrs. Alessandra Tognucci RCC Ltd Environmental Chemistry & Pharmanalytics CH-4452 ltingen/Switzerland Page2

Under Study848638, RCC was supposedto determinethe hydrolysis of DEA/Acid anhydride reaction product at different pH values according to OECD Guideline No. 111 and EEC Directive 92/69, C.?, respectively. DEAl Acid anhydride reaction product is a complex mixture of different monomers, dimers, trimers and polymers. According to the guidelines, the hydrolysis test is only applicable to pure compounds. The hydrolysis determination of a complex mixture is not possible during one single test. If the hydrolysis behaviour of DEAl Acid anhydride reaction product ought to be determined, this must be performed with each of the respective pure substance in a separatetest. Furthermore, it is expected that itwill not be possible to follow properlythe disappearance of some ingredients if the hydrolysiswould be determined in the mixture. Dimers may hydrolyse to monomers and trimers may hydrolyse to dimers and monomers. During polymer hydrolysis, dimers or trimers could be formed as intermediates from polymer hydrolysis which would make it difficult to determine a reasonable hydrolysis kinetics for .these intermediates. It is also beyond the scope of the guidelinesto investigate complex hydrolysis kinetics. Additionally, this mixture cannot be analysed with one single chromatographic technique. Several techniques like size exclusion chromatography, ion chromatography, derivatization followed by HPLC analysis and conventional reversed phase HPLC were used for the analysis of the mixture. Different detectors had to be used for the detection of the components: refractive index detector, conductivity detectorand UV detector. It is considered that the analytical methods are not suitable to follow a hydrolysis of the mixturewith exception of the monomers.RCC Study Number848638 DEA/Acid anhydride reaction product EXPERTSTATEMENT Page 8 Forthe hydrolysis of the mixed ester/amidetrimers, only ester hydrolysiswas relevant forthe rate determining step. Amides were estimated to be stablewith half-lives> 1year. Ester hydrolysis at pH 8 is estimatedto proceed slower byafactor of 1 0 compared to pH 9. It is expected that polymers will be only susceptible to ester hydrolysis at pH 8 and 9. However, some ester functional groups may be shielded or sterically hindered that they are much less suscessible for hydrolysis. 

### Conclusion The test item mixture DEAl Acid anhydride reaction product was not suitable to perform a hydrolysis test according to the OECD guideline 111 and EEC Directive 92/69, C.7, respectively. The method was not applicableto a complex mixture of differentcompounds. QSAR based estimatesforthe acid- and base-catalysed hydrolysis rate led tothe conclusion that DEA/Acid anhydride reaction product will not hydrolyse in an slightly acidic to neutral aquatic environment (pH 4 to pH 7). Under these conditions both ester and amide type functional groups of dimers, trimers and polymers of DEAl Acid anhydride reaction product were estimatedto be hydrolyticallystable. Underalkaline conditions of pH 8to 9, only estertypefunctional groups oftrimellitic acid with · diethanolamine are expected to be hydrolysed. Amides and esters of tetrahydrophtalic acid were estimated to be stable at these pHs. Hydrolysis of mixed ester/amide trimers will lead to stable amide linked dimers, diethanolamine and trimellitic acid as products. Ester linked dimers and trimers of trimellitic acid with diethanolamine are expected to hydrolyse to the corresponding monomers with estimated half-lives of about 0.5 to 3 days at pH 9 and about 5to 30 days at pH 8.



### References [1] [2] W.J. Lyman, W.F. Reehl, D.H. Rosenblatt: Handbook of Chemical Property Estimation Methods, American Chemical Society, 1990. Estimation Program Interface (EPI) Suite Version 3.11, U.S. Environmental Protection Agency, HYDROWINTM, June 10,2003.RCC Study Number848638 EXPERT STATEMENT DEAl Acid anhydride reaction product
RCC Environmental Chemistry

### &Pharmanalytics Mrs. AlessandraTognucci Study Director Dr. Jorn SchreitmOIIer ManagerofAnalytical Chemistry



### A -,:b. 

### J 

# l '\



## -·~· 

# '
.....o.J..()

**~-tAJ.JA.l** ...



# '\~:**t~**

# (tp•':\ OL 

# \J Page9